The Ontario Provincial Police confirm they conducted a search Wednesday as part of their investigation into allegations that the former premier’s staff deleted key emails related to the gas-plants scandal.

A report by the province’s privacy commissioner previously found that members of Dalton McGuinty's staff deleted emails they weren’t supposed to, which related to the cancelled Oakville and Mississauga gas-fired power plants.

The police launched a criminal investigation eight months ago, after Tories made complaints about the deleted emails.

While police won't say where the search on Wednesday occurred, the Ottawa Citizen is reporting that it took place at a data storage facility in Mississauga.

Cancellations could cost more than $1B

Ontario's auditor general has estimated that the full cost of cancelling and relocating the Oakville and Mississauga plants will likely top $1 billion, when long-term costs are included.

In addition to the criminal investigation, a legislative committee is also probing the costly cancellation of the two gas plants.

Reams of emails have been released during the committee probe, some of which have revealed embarrassing details of the political motivations behind the scrapping of the gas plants.

Premier Kathleen Wynne's office didn’t comment specifically on Wednesday’s search, but said that she had been "open and transparent" about the gas plants and would "continue to co-operate fully in any effort to gather information."

New Democrat MPP Gilles Bisson, who sits on the legislative committee, said Wednesday’s revelations prove there is still more to the story.

"This is deeply, deeply troubling," he told CBC News.

Progressive Conservative critic Vic Fedeli said that he supports charges being laid, if police find evidence of criminal wrongdoing during their investigation.

"If documents were deleted … somebody should be charged," he said Wednesday.

With reports from the CBC's Genevieve Tomney and The Canadian Press